Monday, October 27, 2014

Ebola: What Every American Needs to Know

Ebola: What Every American Needs to Know

Ebola is a killer, but it is not very contagious and not a threat in the United States.

Ebola
is a frightening disease, no question. It kills more than half the
people it infects, and there is no cure. Fueling fears is the latest
news that a doctor in New York City has tested positive for the virus,
marking the fourth time someone in the United States has been diagnosed.
But here’s an important fact: Most people in this country shouldn’t be
worried about getting Ebola.

If you are not a health worker or, for some other reason, in direct physical contact with someone who has Ebola, you are not at risk of getting it. Here’s what we know:

While Ebola is deadly, it is not very contagious.
The flu virus is carried through the air, but the Ebola virus is not.
You have to be in physical contact with a sick person and get their
blood or vomit or feces on your skin.

Even in areas of Africa where
the outbreak is spreading out of control, each sick person infects only
two others on average. That is called the R-nought value. It is a
measure of how contagious a disease is. Compare it to measles, for
example, which is airborne like the flu. The R-nought for measles is 18,
meaning each sick person infects 18 others on average during an
outbreak.

Of course, even an R-nought of two is serious if the virus is allowed to spread unchecked. One person infects two, who infect four, then eight, sixteen, etc.

That is what is happening in West Africa. In Liberia, Guinea and
Sierra Leone, the public health systems were not able to contain the
outbreak, so it has become an epidemic. But that could not happen in
this country, which has a robust public health system. Even if more
Ebola-infected people come here, we can be sure the virus will be
contained.

We’re seeing that system at work right now. Everyone who came in
contact with Thomas Duncan, the only person to die of Ebola in this
country, was tracked down and monitored for 21 days, which is the
maximum incubation period for the virus. All of them have now been
cleared of risk.

Duncan did infect two other people; nurses who cared for him in
Dallas. So everyone they had contact with was also traced, and those
people are also being monitored for 21 days.

But while Ebola is not very contagious, it is highly infectious. One
drop of an infected person’s blood may hold a million virus particles,
far more than most viral diseases. And you do not need to have a cut on your skin to become infected. It’s enough that the virus come in contact with skin.
That is why health workers treating Ebola patients must be gowned
head to toe and must follow strict protocols when removing the
contaminated garments. It is also why so many health workers in Africa
have died.

Thomas Duncan was infected because he helped to carry a woman who was
dying of Ebola to the hospital in Liberia. He also carried her back
home when that hospital turned her away for lack of space. The two
nurses who treated him in Dallas were apparently infected because their
gowns left some skin exposed.

So what is your risk? We’re heading into the holiday shopping season. Should you worry
about crowded shopping malls or public transportation? The short answer
is no. Even if you find yourself on a crowded bus next to someone who
seems sick, what you need to worry about is catching the flu, not Ebola.